call_test.go

@@ -94,6 +94,17 @@ func TestCallSupportsSixArguments(t *testing.T) {
 	}
 }
 
+func TestCallSupportsBufferArgument(t *testing.T) {
+	t.Parallel()
+
+	buffer := NewBuffer(4)
+	defer buffer.Free()
+
+	if err := Call(callBufferArgumentFunction(), buffer); err != nil {
+		t.Fatalf("expected success, got error: %v", err)
+	}
+}
+
 func TestErrnoMapping(t *testing.T) {
 	t.Parallel()
 

call_test_support.go

@@ -22,6 +22,10 @@ int call_six_args(uintptr_t a0, uintptr_t a1, uintptr_t a2, uintptr_t a3, uintpt
     return 13;
 }
 
+int call_buffer_argument(uintptr_t value) {
+    return value == 0 ? 13 : 0;
+}
+
 uintptr_t call_sum_length_ptr(void) {
     return (uintptr_t)&call_sum_length;
 }
@@ -33,6 +37,11 @@ uintptr_t call_failure_ptr(void) {
 uintptr_t call_six_args_ptr(void) {
     return (uintptr_t)&call_six_args;
 }
+
+uintptr_t call_buffer_argument_ptr(void) {
+    return (uintptr_t)&call_buffer_argument;
+}
+
 */
 import "C"
 
@@ -53,6 +62,11 @@ func callSixArgumentFunction() unsafe.Pointer {
 	return *(*unsafe.Pointer)(unsafe.Pointer(&function))
 }
 
+func callBufferArgumentFunction() unsafe.Pointer {
+	function := C.call_buffer_argument_ptr()
+	return *(*unsafe.Pointer)(unsafe.Pointer(&function))
+}
+
 func callWithErrnoZero() (int, error) {
 	return WithErrno(func() C.int {
 		return 0

string_conversion.go

@@ -215,6 +215,11 @@ func toSyscallArg(value interface{}) (uintptr, bool) {
 		return 0, true
 	case uintptr:
 		return typed, true
+	case *Buffer:
+		if typed == nil {
+			return 0, true
+		}
+		return uintptr(typed.Ptr()), true
 	case unsafe.Pointer:
 		return uintptr(typed), true
 	case C.char: